• Journal of the Korean Institute of Navigation
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• v.24 no.5
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• pp.417-422
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• 2000

The 3rd order intermodulation(IM3) signals affect a great influence on fundamental signal because IM3 can not be rejected by a filter. To solve this problem, in this paper, a predistortion method was applied. The designed predistorter cascaded to 4 W power amplifier and tested with two-tone spreaded 5 MHz. As an experimental result, it was cleary shown that the 3rd order intermodulation distortion characteristics has been improved as much as 17 dB when the output of the power amplifier is 30.67 dB.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.04a
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• pp.230-233
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• 1987

A Dual Disital Phase Locked Loop is analyzeddesigned and tested. Two specific confisurations are considered generations second and thisrd order DPLL’s and it is found using a computer simulation and verified therretically . As a result of computer simulation the characteristcof designed I-Dullis better than the at of P-DPLL or C-Dull

• BMB Reports
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• v.31 no.4
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• pp.409-412
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• 1998

We isolated and sequenced a human retina cDNA fragment that encodes 25 kDa thiol peroxidase. A search of a databank showed that the 25 kDa thiol peroxidase from retina is the same type of thiol peroxidase which exists in human brain and red blood cells. This type of tbiol peroxidase was distributed in all of the tested tissues including retina. This result suggests a physiological role for the 25 kDa thiol peroxidase as an important antioxidant.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.6
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• pp.745-752
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• 2003

Injection technology is one of the important technologies in a diesel engine. Many studies have done on the injection system. In this study, the fuel chamber geometry, the orifice ratio and the needle lift of the injection valve of a diesel engine for generating electricity are varied and tested. The injection pressure, duration and spray shapes are produced with pressure transducer, needle lift sensor and highspeed camera. The result shows that the nozzle hole size has influence on the rail pressure and injection duration sensuously.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1994.10a
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• pp.157-164
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• 1994

Finite element analysis of material deformation is successfully utilized to understand metal forming processes such as forging, extrusion and deep drawing. However, such analysis involves contact problems; a free node touches a die surface and a contact node slips along the die surface. In the present investigation, appropriate contact algorithms were developed assuming that a three dimensional surface can be divided into bilinear patches and that nodal velocities are linear during an incremental time. The algorithms were coded into a computer program and tested for a simple surface. Comparison of the test result with that obtained from a commercial code is presented and discussed.

• Magazine of the Korean Society of Agricultural Engineers
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• v.21 no.1
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• pp.63-77
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• 1979

Six kinds of weathered granite soils whose degree of weathering and mineral compo- sitions are different, were tested in order to improve the soil-cement. by performing compression test, durability (freezing-thawing) test and mesurement of shrinkage are made. From result of the tests as mentioned above, the following conclusions are drawn. The unconfined compressive strength of seondary additives containing soil-cement mixtures and their resistance against freezeing-thawing are more increased and shrinkage is more decreased than soil-cement mixtures only in case opitimun quantity of additives are added to soil-cement mixtures, and according as types of soils.

• Environmental Analysis Health and Toxicology
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• v.15 no.1_2
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• pp.13-18
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• 2000

A few in vitro methods were developed to compare the result on the phototoxicity of phenothiazines. By the MTT assay, the Candida test, and the RBC photohemolysis, the phototoxicities of UVA and UVB irradiation were measured. This paper presents the comparisons of methods which are effective to measure the phototoxicities of the chemicals causing phototoxicity and photoallergy. The tested chemicals of phenothiazines include Chlorpromazine, Promethazine, Perphenazine, Chlorprothixene, Trifluoperazine and Thioridazine. Each chemical represented variable results according to the test methods. MTT assay shows the most sensitive method.

• Proceedings of the Korea Multimedia Society Conference
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• 2012.05a
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• pp.6-9
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• 2012

In this study, we compare two image denoising methods which are the Rudin-Osher-Fatemi total variation (TV) model and the nonlocal means (NLM) algorithm on medical images. To evaluate those methods, we used two well known measuring metrics. The methods are tested with a CT image, one X-Ray image, and three MRI images. Experimental result shows that the NML algorithm can give better results than the ROF TV model, but computational complexity is high.

• Elastomers and Composites
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• v.31 no.5
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• pp.347-352
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• 1996

A natural rubber was blended with a butadiene rubber with different ratios. A natural rubber, along with three different blends, its ratio varying from 10 to 15 to 20 weight %, were prepared and tested. It was found that inclusion of the butadiene rubber increased cure time, compared to the natural rubber. It is speculated that increased free volume due to the inclusion of butadiene rubber contributed to this effect. Furthermore, inclusion of butadiene rubber led to increase hardness of a sphere, and as a result, the extent of rebound increased sharply.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.12B no.1
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• pp.7-12
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• 2002

This paper presents a method to estimate an effective length of a 1000-kVA superconducting generator using three-dimensional FE analysis. Flux linkage of stator coil and the induced voltage are calculated with FEM program and Faraday's law. An effective length of the stator coil is estimated using the calculated voltage and geometric configurationn of the machine. In order to verify the estimation method, 30-kVA superconducting generator is built and tested. The test result agrees reasonably well with the estimation.